Raft of floating pontoons



-Aug. 6, 1929. SMITH 1,723,213

RAFT OF FLOATING PONTOONS Filed March 19, 1928 INVENTOR AUGUSTUS SMITHby 222': 4220292 {ya Patented Aug. 6, 1929.

UNITED STATES I 1,723,213 PATENT. OFFICE. i

AUGUSTUS SMITH, OF ROSELLE, JERSEY, ASSIGNO R TO BERGEN POINT IRONWORKS, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY.

RAFT OF FLOATING PONTOONS. 7

Application filed March 19; 1928.- Serial No. 262,884.

This invention relates to rafts and more particularly to rafts supportedby pontoons.

An object of the invention is to provide an in'ip'roved floatingplatform or deck to carry a house or for other purposes. A furtherobject is to make possible the construction upon a raft of asuperstructiu'e, which shall be free from distortion by irregularplunging of the pontoons subject to wave motion. Still a further objectis to provide a convenient construction in which the pontoons may beremoved for painting without transferring the entire raft to a drydockormariue railway. Other objects Will appear upon consideration of thisspecification.

The invention is shown by way of illustration I in the accompanyingdrawings, wherein Figure 1 is a side view showing one of the saddlegirders forming part of the raft and the pontoons which support it, I

Fig. 2 is a plan view of a raft constructed in accordance with theinvention from which the flooring and floor joists have been removed, I

,. Fig. 3 a fragmental view showing one method of attaching a pontoon toa girder supporting the raft,

Fig. 4f is a fragmeutal View showing a saddle girder and connections, I

Fig. 5, illustrates one of the cross girders which may be employed inbuilding the raft,

Fig. 6, shows one form of saddle girder and connections, and i F 7,shows another form of saddle girder and connections.

An, important feature of the invention consists in providing ageometrical plane in which lie the axis of a saddle girder carried by anumber of pontoons andthe pivotal point of a second saddle girder whichis free to rock as the pontoons are acted upon by wave motion.

Referring now more specifically to the drawings, three or more pontoonsP, preferably cylindrical in form and of hollow metal, are yokedtogether by a saddle cross girder S. The saddle cross girder S, supports at each end a loi'igitudinal girder L, which. extends the wholelength of the raft and forms its apparent side. Another saddle girder Sis disposed between a pair of simple cross girders G G which in turnsupport the loz'igitudinal girders T and the weight is transmitted fromthe pair of simple cross girders G G to the saddle girder S through apin or axle bolt A on which the cross girders G and the saddle girders Sare free to rock with respect to each other to accommodate themselves towave motion (see particularly'l igs. 2 and 4t).

End girders G connect the ends of the longitudinal girders L and formapparent ends of the raft. One or more additional cross girders Gdepending upon the size of the raft, are connected betweenthe'longitudinal girders L and span over the pontoons, but do not touchthem (see Fig. 5). The cross girders G provide convenient means forcarrying the floor load to the longitudinal girders constituting aspanto which,if desired, wooden floor joists may be connected. Suchfloor joists may be in sorted between an end girder Gr and a crossgirder G at one end of the raft and between the other end girder G, andthe saddle girder S at the other end of the raft, and also between thesaddle girder S and the intermediate cross girder G, and between theintermediate cross girder (i and other intermediate cross girders G ifthe raft is sufficiently long, or between the intermediate cross girderG and the cross girder G if the raft is constructed as illustrated inFig. 2. I

It will thus be seen that this construc tion provides a frame in whichthe axis of the saddle girder S and the pivotal point of the axle bolt Aboth lie in a plane. This plane defined by a line (the axis of'thcsaddle girder S) and a' point (the pivotal point of the axle bolt)outside of that line. The construction described is in effect a threepoint suspension. It provides a frame upon which a floor can be laid. Asuperstructure erected upon this fioor Will be free from distortion byirregular plunging of the pontoons when subjected to wave motion.

If the Wave motion to be encountered, is of serious magnitude, theoutside pontoons, shown in Fig. 1, may be made of smaller diameter thanthe central pontoons thereby affording a greater are for rocking of thesaddle girders S without striking the floor of the raft and withouthaving the cross girders G strike the outside pontoons.

To provide for still greater wave motion, it may be desirable to employan uneven number of pontoons, the centre pontoon being of largerdiameter than the outside pontoons as illustrated in Fig. 6, in which aconstruction employing three pontoons is shown. Where more than threepontoons are employed their diameters may be progressively decreasedfrom the centre of the raft outward, as shown in Fig. 7. lnconstructions of this character, I prefer to build the saddle girder Swith a curved top so as to permit of the maximum free rocking motionabout the axle pin A, without interference with the floor of the raft.

In order to provide a convenientway of painting or otherwise caring forthe pontoons without removing the entire raft to a drydock or marinerailway, it is possible to attach the pontoons to the saddle girderswithout rigidly fastening them thereto- F or this purpose I prefer toconnect thepontoons loosely to the saddle girders, depeinfling largelyupon-the buoyancy of the pontoons under normal conditions formaintaining contact. A hinged pin or bolt of any kind may be used, suchfor instance, as the hinged pin B illustrated in Fig. 3, which isdropped into a hole or socket H in the pontoon. 'lhe constructionillustrated is suilicient to pre vent the pontoons from rolling underthe saddle girders or to prevent longitudinal motion with respect to thesaddle girders. The only objection to fastening the pontoons moresecurely to the saddle girders is the trouble required to disconnectthem.

Means may also be provided for altering the buoyancy of the pontoons,either by admitting water to them or by adding weight. Thus theirremoval from beneath the saddle girders will be facilitated. Such meansmay consist, for instance, of two valves one on top of, and one beneaththe pontoon. Such valves are illustrated by way of example by theelements V and V in Eigs. 2 and 8.

When it is desired to remove the pontoons, as for painting, in the caseof a four pontoon raft as shownin Fig. 1, the two outer or the two innerpontoons or any one pontoon may be submerged by admitting water theretoor otherwise adding weightso as to sink it free of the saddle girders.The pentoon is disconnected from the saddle girders for instance bylifting the-bolt B shown in 3 clear of the hole or socket H. Theweighted pontoon, having lost buoyancy, may then be pulled out fromunder the raft, pumped relieved or weight, and rolled up on a beach on apair of skids where it can be conveniently painted or otherwiserenovated. After painting or renovation, the pontoon may be restored toits position under the raft by reversing the process which has just beenindicated.

In the case of a four pontoon raft the buoyancy of the pontoons shouldbe sufficient ree of ballast water or other for any two to carry theload safely, while the other two are out of service. In the ease of athree pontoon raft, as shown in G, the central pontoon would have toprovide sufficient buoyancy to carry the whole load alone while thesmaller wing pontoons were being docked. in the latter case only onewing pontoon should be removed at a time, the other being retained withtemporary lashings or fastenings to the saddle girders, in order that itmay pull down well as lift up and thus prevent the raft from capsizing.In this latter arse the two outer pontoons, together, should providesutiicient buoyancy to float the raftwhile the central pontoon istemporarily removed. in the case of a raft supported by i *e or moreponteons, such as that shown in T, docking would obviously be easier.

c aim:

in a raft,

a plurality of pontoons, and

a rrameworlr, in combination with a saddle girdle supported by saidpontoons rigidly ted to said framework, and a second saddle girdersupported by said pontoons pivotally connected to said framework.

2. In a raft, a plurality of pontoons, and a framework in combinationwith a saddle girder supported by said pontoons rigidly connected tosaid framework near one end thereof, and a second saddle girdersupported by said pontoons pivotally connected to said framework nearthe other end thereof.

In a raft, a plurality of pontoons, a framew rk, and a saddle girderrigidly connected to said framework, in combination with a second saddlegirder, and an axle bolt, pivotally connecting the mid-point of saidsecond saddle girderto said framcw rk, substantially as described.

l. in a raft, a plurality of pontoons, and a framework, in combinationwith a saddle 'Jder supported by said pontoons rigidly niected to saidframework, a second saddle pported by .aid pontoons pivotally irder su'onnccted to said f 'aine 'ork, and means for detachably connecting saidpontoons to said saddle girders.

5. In a raft, a

aframework, in combination with a saddle plurality of pontoons, and

U 'der supported by said pontoons rigidly connected to said framework, asecond saddle girder supported by said pontoons pivotally conneiaed tosaid framework, and means for detachably coni'iecting said pontoons tosaid saddle girders, and other means for altering the buoyancy of said.pontoons, substantially as described.

in testimony whereof I have signed my name to this SPGClfiCZltlOn.

AUGUSTUS SMITH.

